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Published on: October 25, 2017
New β-strand templates constrained by Huisgen cycloaddition.
Ashok D Pehere1, Andrew D Abell
1School of Chemistry & Physics, The University of Adelaide, North Terrace, Adelaide SA 5005, Australia.
Organic Letters
|February 21, 2012
Summary
New peptidic macrocycles mimic beta-strand structures, acting as potent calpain protease inhibitors. These novel templates offer versatile applications for targeting various proteases.
Area of Science:
- Medicinal Chemistry
- Organic Chemistry
- Biochemistry
Background:
- Protease inhibitors are crucial therapeutic agents.
- Constrained peptide conformations can enhance target specificity and potency.
- Beta-strand mimetics offer a promising scaffold for drug design.
Purpose of the Study:
- To develop novel peptidic templates that adopt a stable beta-strand conformation.
- To investigate the inhibitory activity of these templates against the protease calpain.
- To establish optimized conditions for the synthesis of these constrained peptides.
Main Methods:
- Synthesis of tripeptides with acetylene and azide functionalities.
- Huisgen cycloaddition to form macrocyclic peptidic templates.
- Nuclear Magnetic Resonance (NMR) studies to determine macrocycle conformations.
- Enzyme inhibition assays to evaluate calpain inhibition.
Main Results:
- Successfully synthesized novel peptidic macrocycles constrained into a beta-strand geometry.
- NMR analysis confirmed the defined conformations of the macrocycles.
- Templates adopting a beta-strand conformation demonstrated potent inhibition of calpain.
- Optimized synthetic conditions were established for template preparation.
Conclusions:
- The developed peptidic templates effectively mimic beta-strand structures.
- These constrained peptides are potent inhibitors of calpain.
- The synthetic methodology is adaptable for targeting other proteases and applications requiring beta-strand geometry.
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